Inner enclosure with micro shock absorber for a carrying case

ABSTRACT

An improved soft inside enclosure for shock protection of a variety of external electronic and computer peripheral comprises a set of substantially evenly spaced small columns of Micro Shock Absorber (MSA) protrusions that are integrated on the inside surfaces of the soft inside enclosure. Additionally, the base wall of the MSA structure can include a set of micro venting features for the improvement of heat dissipation from the enclosed devices to the ambient. A number of specific candidate materials are also presented for the construction of the soft inside enclosure with the MSA structure. A method for the systematic and experimental determination of a specific design of the MSA structure based on its durometer, thickness, diameter, column height, and pitch are disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This invention is a formal application of a provisionalapplication, filed on Dec. 18, 2000, Serial No, 60/256,735 and acontinuation application filed Sep. 19, 2001, Ser. No. 09/956,727.

FILED OF INVENTION

[0002] This invention relates to a new design of a soft inner enclosurefor the carrying case of an external data storage device or otherelectronic devices for shock protection of the external data storagedevice or other electronic devices in their storage, carrying andoperating mode.

BACKGROUND OF INVENTION

[0003] The need of an enclosure for the protection of a variety ofdevices against shock has been around for a long time. A brief searchand analysis of the prior art revealed the following US patents:

[0004] U.S. Pat. No. 4,786,121 (November 1988, by Lyons), titledcomputer protective enclosure, teaches the usage of outside panels withinner linings to acoustically isolate and additionally protect thestored computer. The outside panels, or covers, are made of rigidmaterials such as wood, plastic and metal. The inner linings are made offoam plastic with a space between the inner linings and the computer.Furthermore, the enclosure is intended for affixing to buildingconstruction members or other stationary objects for stability.

[0005] U.S. Pat. No. 4,846,340 (July 1989, by Walther), titled shockproof carrying enclosure for musical instrument, teaches the usage of anenclosure for the shock proof storage and carrying of a musicalinstrument like cello. However, in this case, the enclosed musicalinstrument is already retained within a rigid case to begin with.Therefore, effectively, the protective structure for the musicalinstrument itself consists of an inner rigid case and an outer flexibleenclosure.

[0006] U.S. Pat. No. 5,010,988 (April 1991, by Brown), titled expandableshock protected carrying case, teaches the usage of a carrying case fora lap top computer, printers, facsimiles and the like where the carryingcase comprises of functional elements like handle, shoulder strap,compartments and accessory pockets. The disclosed wall structureconsists of at least three layers, that is, an outer shell, an innershell and a three-ply shock protection structure sandwiched in between.The outer shell is made of a substantially rigid yet soft material. Thedisclosed carrying case looks to be primarily used when the encloseddevice is in its non-operating mode. Thus, for example, thermallyinsulating materials and related structural design are employed there toprotect the enclosed device from temperature extremes.

[0007] U.S. Pat. No. 6,034,841 (March 2000, by Albrecht, Khanna, Kumarand Sri-Jayantha), titled disk drive with composite sheet metal andencapsulated plastic, describes the usage of a metal base withintegrally molded plastic peripheral flanges plus elastomeric comerbumpers for shock protection. As described, except for the elastomericcomer bumpers, all the other enclosure pieces are made of rigidmaterial.

[0008] As described in a pending application filed earlier by theinventor, a soft enclosure design for an external data storage device orother electronic devices in their storage, carrying and operating modeis disclosed. The inside shock absorbing layer of the soft enclosuredesign, now called inner enclosure for simplicity, provides manyfunctions. Some examples of the functions are shock protection, heatdissipation, fire retardation, shielding against radio frequencyinterference, prevention of build up of static electricity andprevention of dirt penetration into the interior of the enclosure. Thisinvention deals with a more specific design of the inner enclosure withadditional merits. For clarity, it is remarked that the inner enclosureis also commonly referred to as the inner lining for a carrying case.

SUMMARY OF INVENTION

[0009] The current invention is conceived to realize a more specificdesign of the inner enclosure, or the inner lining for a carrying case,of an external data storage device with additional merits. Specifically,it is an objective of this invention to provide an inner enclosure foran external data storage device whereby the function of shock protectionfor the data storage device is achieved by using a minimum amount ofmaterials thus saving manufacturing cost and reducing the associatedproduct weight.

[0010] It is another objective of this invention to provide an innerenclosure for an external data storage device whereby improved heatdissipation for the data storage device is achieved by using a minimumamount of materials thus saving manufacturing cost and reducing theassociated product weight.

[0011] A third objective of this invention is to provide an innerenclosure for an external data storage device whereby the functions offire retardation, shielding against radio frequency interference andprevention of build up of static electricity are achieved with aselection of specific materials for the inner enclosure.

[0012] Accordingly, the invention disclose a new design of the innerenclosure for the carrying case of, but without limitation to, anexternal data storage device as mentioned in the said prior application.The inner enclosure is made of a soft shock absorbing material andprovides for a snug fit and an all around shock protection for theenclosed data storage device in both non-operating and operating modes.The inner enclosure consists of a device compartment and a removablecover. Once the inner enclosure is completely closed within an outerenclosure, the inner enclosure will provide a snug fit to the encloseddevice all around. For good shock absorption while using a minimumamount of material, the inner surface of the inner enclosure isconstructed with an array of substantially evenly spaced miniaturecolumns called Micro Shock Absorber (MSA). In addition to shockprotection, the MSA also provides air circulation to the enclosedstorage device by creating a thin air space between the device and theinner enclosure. As needed, the material of the inner enclosure can beselected to be fire retardant, shielding against radio frequencyinterference, preventing build up of static electricity, allowing betterheat dissipation from the data storage device while preventing dirtpenetration into the interior of the enclosure.

BRIEF DESCRIPTION OF DRAWINGS

[0013] The invention is explained in full detail with the followingdetailed description of the preferred embodiments, with reference madeto the accompanying drawings, wherein:

[0014]FIG. 1 is one perspective illustration of a commonly practicedprior art wherein two rigid covers with mounting means are employed toenclose a storage device;

[0015]FIG. 2 is one more perspective illustration of a commonlypracticed prior art wherein two rigid covers with mounting means areemployed to enclose a storage device;

[0016] FIGS. 3A-C are perspective illustrations of the current inventionwherein two soft inner enclosures, or alternatively called innerlinings, are employed to enclose a storage device;

[0017]FIG. 4 is a perspective illustration of the current inventionwherein the details of the MSA structure and its associated designparameters are shown;

[0018] FIGS. 5A-B are comparison of the wall structure between atraditional and the current design of the inner enclosure with designparameters illustrating the benefit of materials saving with the currentinvention;

[0019]FIG. 6 illustrates an additional embodiment of the currentinvention wherein a set of micro venting slots are added to the wallstructure of the current invention with MSA for further improved heatdissipation;

[0020] FIGS. 7A-B are additional perspective illustrations of thecurrent invention wherein a fully enclosed storage device, within twosoft inner enclosures with MSA, similar to that illustrated in FIG. 3Cis progressively shown to be loaded into a soft outside enclosure; and

[0021] FIGS. 8A-B are the final perspective illustrations of the currentinvention wherein the fully enclosed storage device from FIG. 7B isprogressively shown to be fully enclosed with the closure of a softdevice cover and a soft connector cover.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022]FIG. 1 and FIG. 2 are perspective illustrations of a commonlypracticed prior art wherein two rigid covers with mounting means areemployed to enclose a storage device. FIG. 1 illustrates, with twoarrows, the progressive enclosure of a storage device 1 with a storagedevice interface connector 2 and an associated rigid connectorinterchanger 70. The wall material of the storage device 1 is usuallymade of metal to house the precision mechanism inside. The storagedevice interface connector 2, when hooked up, through the associatedrigid connector interchanger 70, with the corresponding mating connectorof a computer not shown here, would provide all the necessary electricalpower and interface signals to insure proper operation of the storagedevice 1. As shown, the storage device 1 will generally be housedbetween a rigid top cover 30 and a rigid bottom cover 40 with a set ofmounting screws 50. The finished product is illustrated in FIG. 2.Usually these rigid covers are made of plastics or metal. Thus, theenclosed storage device 1 is still very susceptible to shock damage asthe rigid covers do not provide any damping protection against shock.

[0023]FIG. 3A, FIG. 3B and FIG. 3C are perspective illustrations of thecurrent invention wherein two soft inner enclosures, or alternativelycalled inner linings, are employed to enclose a storage device. The twosoft inner enclosures are, as shown in FIG. 3A, a soft top innerenclosure 3 and a soft bottom inner enclosure 4. The storage device tobe enclosed by the soft top inner enclosure 3 and the soft bottom innerenclosure 4 is the storage device 1 with a storage device interfaceconnector 2. The storage device interface connector 2, when hooked upwith the corresponding mating connector from a computer not shown here,would provide all the necessary electrical power and interface signalsto insure proper operation of the storage device 1. Many storage device1, such as external or portable hard drives, optical storage devices orcomputers with built in magnetic and optical storage devices, can beeasily damaged when it is dropped accidentally. Thus, the soft top innerenclosure 3 and the soft bottom inner enclosure 4 are used together toprovide protection for the storage device 1 in both operating andnon-operating modes. The soft top inner enclosure 3 consists of a softtop inner enclosure base 9 c whose inside surface has a set of soft topenclosure MSA 17 which will be described in more detail later. The softbottom inner enclosure 4 consists of a soft bottom inner enclosure base9 a, four soft bottom inner enclosure side walls 9 d with a connectoraccess slot 9 b located on one of the soft bottom inner enclosure sidewalls 9 d. Like the soft top inner enclosure 3, the soft bottom innerenclosure base 9 a also has a set of soft bottom enclosure MSA 16located on its inside surface which will also be described in moredetail later. Thus, following the direction of the arrows, the soft topinner enclosure 3 and the soft bottom inner enclosure 4 will provide asnug fit to the enclosed storage device 1 all around except for themechanical accessibility to the storage device interface connector 2through the connector access slot 9 b of the soft bottom inner enclosure4. This is illustrated in FIG. 3B and FIG. 3C.

[0024]FIG. 4 shows more details of the soft top inner enclosure 3 andthe soft bottom inner enclosure 4. To provide for sufficient shockprotection with the proper range of softness, or durometer, the selectedmaterial for the inner enclosure is soft Microcellular Urethane (tradename: PORON), Polyurethane or other material with similar properties.For further enhancement of shock protection, the inside surfaces of bothinner enclosures 3 and 4 are constructed with a set of substantiallyevenly spaced small columns of MSA protrusions. These are soft topenclosure MSA 17 for the soft top inner enclosure 3 and the soft bottomenclosure MSA 16 for the soft bottom inner enclosure 4. As the MSA andthe inner enclosure body are made of the same material, the MSA can beeasily casted or molded as part of the enclosure in volume production.Furthermore, as neither the MSA nor the inner enclosure body requireshigh dimensional accuracy, the need of expensive tooling for the cast ormold is eliminated.

[0025] The amount of shock protection provided by the MSA dependsprimarily on the following parameters: the durometer of theMicrocellular Urethane, the MSA base thickness T, the MSA diameter D,the MSA height H, the MSA pitch P as well as the density of the enclosedstorage device 1. In general, the following qualitative designguidelines were discovered: (1) lower durometer of the inner enclosurebase material yields higher shock protection; (2) higher MSA basethickness T yields higher shock protection; (3) larger MSA diameter Dyields higher shock protection; (4) larger MSA height H yields highershock protection; (5) lower MSA pitch P yields higher shock protectionand (6) lower density of the enclosed storage device 1 allows highershock protection.

[0026] However, in practice, the complexity of the involved quantitativefunctional relationship amongst the above design parameters is found tobe too complicated to warrant a mathematical treatment. Instead, anempirical design must be reached through a set of parametric experimentsfollowing the above qualitative design guidelines. As a quantitativeexample of this invention, we have made the following findings.

[0027] A typical 2.5 inch hard disk storage device can be adequatelyshock protected from a drop height of up to 4 feet onto a hard surfacewith an MSA structure of the following parametric design: (1) innerenclosure base material is Microcellular Urethane; (2) durometer of theinner enclosure base material is 30 durometer; (3) MSA base thicknessT=6.4 mm; (4) MSA diameter D=7 mm; (5) MSA height H=4 mm height; (6) MSApitch P=17 mm.

[0028] Another point to be made here is that, given the aforementionedcomplexity of the functional relationship among the design parameters,multiple combinations within a range of parameters exist for the samedesired shock protection. For example, in the above case, an MSAdiameter D from 6 mm to 8 mm and an MSA height H from 4 mm to 5 mm wouldall produce similar shock protection.

[0029] A subtle but important benefit of the current invention isillustrated in FIG. 5A and FIG. 5B. FIG. 5A represents a prior art innerenclosure wall structure 20 which is plain while FIG. 5B represents thecurrent invention with the MSA wall structure 21 optimized for a minimumoverall thickness of the MSA structure T+H, for a specified amount ofshock protection. While the prior art inner enclosure wall structure 20has the same overall wall thickness S=T+H as the current invention, itwas found that the prior art design can not provide the specified amountof shock protection as does the current invention. The reason is that,upon impact of the enclosed storage device with an external object, thenumerous soft bottom enclosure MSA 16 of the current invention act as aninitial spacer during the first stage of the shock absorption processwhere most of the associated kinetic energy is dissipated. That is, onlythe soft bottom enclosure MSA 16 go through related geometricdeformation to dissipate the kinetic energy while the enclosed storagedevice stays free of contact with the soft bottom inner enclosure base 9a. While the storage device still contacts the soft bottom innerenclosure base 9 a during the second, or last, stage of the shockabsorption process, by this time the remaining kinetic energy to bedissipated is significantly lower than its value during the first stage.In summary, given the same specified amount of shock protection and thesame overall wall thickness, the net kinetic energy to be dissipatedupon impact by the enclosed storage device with the current inventionwould be significantly less than that with a traditional prior artdesign. Or equivalently, given the same specified amount of shockprotection, the current invention will provide a design which has asignificantly less overall wall thickness than the traditional design.This translates into an advantage of size and weight reduction with thecurrent invention. Furthermore, given the MSA structure, the net volumeoccupied by the shock absorbing material is significantly less than thatenclosed in the overall wall thickness T+H, this translates into anotheradvantage of weight reduction with the current invention. A thirdadvantage of the current invention is that, upon closure of the soft topinner enclosure 3 and the soft bottom inner enclosure 4, a thin airspace is formed between the enclosed storage device 1 and the innerenclosure with MSA wall structure 21. The thin air space thus providesthe function of air circulation resulting in a more uniform distributionof heat from the storage device 1 for a more efficient heat dissipationto the outside ambient.

[0030]FIG. 6 illustrates an additional embodiment of the currentinvention wherein the inner enclosure with MSA wall structure 21 has aset of substantially evenly spaced micro venting slots 22 cut throughits wall to further improve heat dissipation to the outside ambient. Ofcourse, the cross section of these venting features does not have to bea slot. For example, it can be a circle, an ellipse or any other shapeas long as easy manufacturability is maintained.

[0031] Finally, Microcellular Urethane, one of the selected material forthe inner enclosure with MSA, possesses additional physical propertieswhich are important or beneficial to the enclosed storage device.Microcellular Urethane has low memory effect, which is important for thepreservation of the MSA geometry after long termed usage or storage ofthe storage device. Microcellular Urethane is reasonably heat conductivewhich helps the dissipation of heat from the storage device. It does notaccumulate static electricity thus provides good ESD protection for thestorage device. It is fire retardant with UL-approval for a safeproduct. It can be metallically coated to shield against EMI/RFI forreliable data transfer.

[0032]FIG. 7A and FIG. 7B are additional perspective illustrations ofthe current invention wherein a storage device is fully enclosed with aset of soft inner enclosures, similar to that shown in FIG. 3C, thestorage device is progressively shown to be loaded into a soft outsideenclosure 8. Following the direction of the arrows in FIG. 7A, the nowenclosed storage device 1 is first loaded into the soft outsideenclosure 8. Afterwards, the storage device 1, now enclosed in bothinner and outer soft enclosures with shock protection, is shown in FIG.7B. Notice that the mechanical accessibility to the interface pins ofthe storage device 1 is maintained through the corresponding connectoraccess slot 9 b of the soft bottom inner enclosure 4 and the connectoraccess slot 15 of the soft outside enclosure 8.

[0033]FIG. 8A and FIG. 8B are the final perspective illustrations of thecurrent invention wherein the enclosed storage device 1 from FIG. 7B isprogressively shown to be fully enclosed like a carrying bag in thenon-operating state of the storage device 1 with the closure of a softdevice cover and a soft connector cover. Following the right hand arrowof FIG. 8A, the soft outside enclosure device cover 12 will be closedwith the movement of the zipper mechanism consisting of two soft outsideenclosure zippers 10 and an outside enclosure zipper handle 11. Finally,following the left hand arrow of FIG. 8A, the soft outside enclosureconnector cover 13 will be closed with the mating of a velcro hook pad14 a to a velcro loop pad 14 b. The final enclosure in the form of acarrying bag is illustrated in FIG. 8B.

[0034] In summary, as illustrated above, a first advantage of thecurrent invention is that, given the same specified amount of shockprotection, the current invention provides an inner enclosure for astorage device whose overall wall thickness is significantly less thanthat of a traditional design. The net result is a size and weightreduction of the product.

[0035] The second advantage of the current invention is that, with theMSA geometry, the net volume occupied by the shock absorbing material issignificantly less than that enclosed within the overall wall thickness.This means additional cost and weight reduction of the product.

[0036] A third advantage of the current invention is that a thin airspace is formed between the enclosed storage device and the innerenclosure with the MSA wall structure. The thin air space thus providesthe function of air circulation resulting in a more uniform distributionof heat from the storage device for a correspondingly more efficientheat dissipation to the outside ambient.

[0037] A fourth advantage of the current invention is that a set ofmicro venting slots are provided on the MSA wall structure to furtherimprove heat dissipation from the storage device to the outside ambient.

[0038] A fifth advantage of the current invention is that the selectedbase material for the inner enclosure has a set of physical propertieswhich result in the following benefits such as preservation of the MSAgeometry after long termed usage or storage of the storage device;improved heat dissipation from the storage device; good ESD protectionfor the storage device; fire retardation with UL-approval and shieldingagainst EMIRFI for reliable data transfer.

[0039] In conclusion, an improved inner enclosure, or alternativelycalled inner lining, with MSA has been described for an external storagedevice providing shock protection, improved heat dissipation plus a setof additional functions while reducing the cost, size and weight of theproduct. The invention has been described using exemplary preferredembodiments. However, for those skilled in this field the preferredembodiments can be easily adapted and modified to suit additionalapplications without departing from the spirit and scope of thisinvention. Thus, it is to be understood that the scope of the inventionis not limited to the disclosed embodiments. On the contrary, it isintended to cover various modifications and similar arrangements basedupon the same operating principle. The scope of the claims, therefore,should be accorded the broadest interpretations so as to encompass allsuch modifications and similar arrangements.

I claim:
 1. A soft inside enclosure of a carrying case for shockprotection of an electronic device in its storage, carrying andoperating modes, comprising: a soft top inner enclosure having a softtop base wherein said soft top base comprises further a set of smallcolumns of protrusions made of a first shock absorbing material; a softbottom inner enclosure having a soft bottom base and four side wallswith a connector access slot located on one of the side walls whereinsaid soft bottom base further comprises a set of small columns ofprotrusions made of a second shock absorbing material; and whereby thesoft top inner enclosure and the soft bottom inner enclosure snug fitthe enclosed electronic device all around to provide for a desirableshock absorption for the enclosed electronic devices.
 2. The soft insideenclosure according to claim 1 wherein said set of small columns ofprotrusions further comprises a set of micro venting features for theimprovement of heat dissipation from the enclosed electronic devices tothe ambient.
 3. The soft inside enclosure according to claim 2 whereinsaid set of micro venting features is selected from the group consistingof a slot, a circle, an ellipse or any other shape suitable for heatdissipation.
 4. The soft inside enclosure according to claim 1 whereinthe first shock absorbing material is selected from the group consistingessentially of soft microcellular urethane, metallically coated softmicrocellular urethane and polyurethane.
 5. The soft inside enclosureaccording to claim 1 wherein the second shock absorbing material isselected from the group consisting essentially of soft microcellularurethane, metallically coated soft microcellular urethane andpolyurethane.
 6. A method of making an soft inside enclosure of acarrying case for an electronic device for providing acustomer-specified amount of shock protection to said electronic devicein its storage, carrying and operating modes, comprising the steps of:providing a soft top inner enclosure having a soft top base wherein saidsoft top base comprises further a first set of substantially evenlyspaced small columns of Micro Shock Absorber (“MSA”) protrusions made ofa shock absorbing material; providing a soft bottom inner enclosurehaving a soft bottom base and four side walls with a connector accessslot located on one of the side walls wherein said soft bottom basefurther a second set of substantially evenly spaced small columns ofMicro Shock Absorber (“MSA”) protrusions made of a shock absorbingmaterial; snagging fit the enclosed electronic device by the soft topinner enclosure and the soft bottom inner enclosure to provide for ashock absorption for the enclosed electronic devices; determining thecustomer-specified amount of maximum shock protection in terms of amaximum allowable non-damaging drop height of the enclosed device and ahardness of a drop surface of impact; measuring the size and weight ofthe enclosed device; and systematically varying a variety of parametersincluding durometer, thickness, diameter, column height and pitch of theMSA until one or more combination of said parameters satisfies saidmaximum allowable non-damaging drop height of the enclosed device uponsaid drop surface of impact with said specified hardness.
 7. The methodof making a soft inside enclosure according to claim 6 wherein theenclosed device is a typical 2.5 inch hard disk storage device.
 8. Themethod of making a soft inside enclosure according to claim 7 whereinthe enclosed device is a typical 2.5 inch hard disk storage device. 9.The method of making a soft inside enclosure according to claim 8wherein the maximum allowable non-damaging drop height is 4 feet and thedrop surface of impact is a hard concrete surface.
 10. The method ofmaking a soft inside enclosure according to claim 9 wherein thedurometer of the MSA is
 30. 11. The method of making a soft insideenclosure according to claim 10 wherein the thickness of the MSA is 6.4mm.
 12. The method of making a soft inside enclosure according to claim11 wherein the diameter of the MSA is 7 mm with an acceptable range of 6mm to 8 mm.
 13. The method of making a soft inside enclosure accordingto claim 12 wherein the column height of the MSA is 4 mm with anacceptable range of 4 mm to 5 mm.
 14. The method of making a soft insideenclosure according to claim 13 wherein the pitch of the MSA is 17 mm.15. The method of making a soft inside enclosure according to claim 6wherein the first shock absorbing material is selected from the groupconsisting essentially of soft microcellular urethane, metallicallycoated soft microcellular urethane and polyurethane.
 16. The method ofmaking a soft inside enclosure according to claim 6 wherein the secondshock absorbing material is selected from the group consistingessentially of soft microcellular urethane, metallically coated softmicrocellular urethane and polyurethane.